title: Compounds enhanced in a mass spectrometric profile of smokers' exhaled breath versus non-smokers as determined in a pilot study using PTR-MS.
abstract: A pilot study has been carried out to define typical characteristics of the trace gas compounds in exhaled breath of non-smokers and smokers to assist interpretation of breath analysis data from patients who smoke with respiratory diseases and lung cancer. Exhaled breath was analyzed using proton transfer reaction-mass spectrometry (PTR-MS) for 370 volunteers (81 smokers, 210 non-smokers, 79 ex-smokers). Volatile organic compounds corresponding to product ions at seven mass-to-charge ratios (m/z 28, 42, 69, 79, 93, 97, 123) in the PTR-MS spectra differentiated between smokers and non-smokers. The Youden index (= maximum of sensitivity + specificity - 1, YI) as a measure for differentiation between smokers and non-smokers was YI = 0.43 for ions at the m/z values 28 (tentatively identified as HCN), YI = 0.75 for m/z = 42 (tentatively identified as acetonitrile) and YI = 0.53 for m/z = 79 (tentatively identified as benzene). No statistically significant difference between smokers and non-smokers was observed for the product ions at m/z = 31 and 33 (compounds tentatively identified as formaldehyde and methanol). When interpreting the exhaled breath of lung cancer or COPD patients, who often smoke, compounds appearing at the above-mentioned seven mass-to-charge ratios should be considered with appropriate care to avoid misdiagnosis. Validation studies in larger numbers of patients with more precise delineation of their smoking behavior and using additional analytical techniques such as GC/MS and SIFT-MS should be carried out.
authors.affiliation: Department of Anaesthesiology and Critical Care Medicine, Innsbruck Medical University, Anichstraße 35, A-6020 Innsbruck, Austria. Breath Research Unit of the Austrian Academy of Sciences, Dammstrasse 22, A-6850 Dornbirn, Austria.
authors.forename: Ievgeniia
authors.initials: I
authors.lastname: Kushch
authors.forename: Konrad
authors.initials: K
authors.lastname: Schwarz
authors.forename: Lukas
authors.initials: L
authors.lastname: Schwentner
authors.forename: Bettina
authors.initials: B
authors.lastname: Baumann
authors.forename: Alexander
authors.initials: A
authors.lastname: Dzien
authors.forename: Alex
authors.initials: A
authors.lastname: Schmid
authors.forename: Karl
authors.initials: K
authors.lastname: Unterkofler
authors.forename: Günter
authors.initials: G
authors.lastname: Gastl
authors.forename: Patrik
authors.initials: P
authors.lastname: Spaněl
authors.forename: David
authors.initials: D
authors.lastname: Smith
authors.forename: Anton
authors.initials: A
authors.lastname: Amann